High Performance Computing and Computational Fluid Dynamics (HPC and CFD))
We are dedicated to developing HPC CFD methods for solving complex PDEs, modeling and simulating fluid dynamics-driven aerospace and mechanical engineering devices.A beautiful CFD simulation of complex fluid dynamics is made possible by rigorously translating physics to partial differential equations (PDEs), developing a suite of robust algorithms and implementing them to accurately and efficiently solve these PDEs on discrete space-time domains, while logically representing the configurations for practical engineering, using the state-of-the-art HPC architectures. A HPC CFD researcher needs to make friends with mathematics, computers, physics, and engineering. One must be meticulous, thorough, and detail oriented. One needs patience, perseverance, and stamina. One must be optimistic, when debugging tough bugs.
This animation is created by Chord, our inhouse CFD solver, showing cellular detonation structures. Initial condition is angled flow with hydrogen-air mixture at M=9.3. An oblique shock develops and heats the gas near the wall. After an ignition delay, the gas near the wall starts burning. Confinement by the wall causes pressure to increase which in turn increases the strength of the deflagration. This causes it to curve and become more normal to the flow. Eventually, the deflagration wave undergoes DDT, deflagration-to-detonation-transition. The gas further to the right is a complex mix of initial perturbations and combustion processes. When fully developed, there is a clear oblique shock, deflagration, and detonation wave. Gas particles experiencing different shock strengths create a slip line. Cellular burning structures can be observed in the detonation wave. The entire process is analogous to unsteady detonation in a detonation tube.
This animation, created by Chord, shows a cold flow of the lean, premixed propane-air mixture in a bluff-body combustor. The color legend is vorticity isosufaces colored by z-velocity, showing the vortex structural development with a background of grid boxes where 3 levels of AMR are used for the region immediately behind the bluff body.
A snapshot from a CFD simulation using Chord, our in-house high-order finite-volume CFD code for predicting a type-4 shock-shock interaction over a blunt body where the boxes are adaptive mesh refinement (AMR) grid boxes without showing the cells.